From the nssldap@padl.com mailing list, Sat 21 Oct 2000:
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Michael Shuey has fixed a race condition in nss_ldap which
caused nscd to lock up under Linux. The patch is in
nss_ldap-121.
See bugzilla.padl.com bug #49 for more info.
-- Luke
--
Luke Howard | lukeh@padl.com
PADL Software | www.padl.com
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The gist of the bug is that nss_ldap has a lock which it takes. If you are
running nscd, it is possible to lock the entire machine by making all nscd
threads call getpw*.
This triggers a race condition, and locks *ALL* entity lookup - "ls -l",
ps, all login utilies - all will block. *IF* you happen to know the PID of
nscd, you can kill it, otherwise, you'll have to power-cycle the machine.
I could reliably trigger this bug using "tar" on a fast machine - the
lookups for the file username, combined with general system activity,
would lock the machine unrecoverably.
nss_ldap version 121 has a fix for this.